Taffit: An Excel Tool for Fitting Tafel Data

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis Research

Background:

• Tafel analysis is crucial for characterizing electrode kinetics in electrochemistry, catalysis, materials, and corrosion research.
• Classical Tafel analysis (CTA) suffers from user subjectivity in selecting linear ranges, leading to significant variations in kinetic parameters.
• A need exists for a more reliable and user-independent method for Tafel analysis.

Purpose of the Study:

• To introduce Taffit, an algorithm for user-independent Tafel analysis.
• To improve the accuracy and precision of determining electrochemical kinetic parameters.
• To provide a more objective method for comparing electrocatalysts.

Main Methods:

• Development of the Taffit algorithm in Microsoft Excel.
• Generation of Tafel plots from linear sweep voltammetric data.
• Determination of exchange current density (j0), charge transfer coefficient (α), and Tafel slopes using statistical fitting.

Main Results:

• Taffit provides user-independent determination of kinetic parameters, reducing variability.
• Taffit yields log j0 values of -7.2 for GC and -3.9 for Pt in HER at pH 0.
• Demonstrated agreement between Taffit and CTA for HER on metal phosphide and selenide electrocatalysts.

Conclusions:

• Taffit significantly reduces subjectivity in Tafel analysis, enhancing accuracy and precision.
• The algorithm offers a more reliable approach for characterizing electrode kinetics, particularly for electrocatalyst comparisons.
• Taffit represents a valuable tool for researchers in electrochemistry and related fields.